During its almost three decade evolution CICS went through at least three major rebirths. The original 1968 product evolved nicely until the advent of virtual storage systems at which time CICS Development did major rework of the product to deal with the significantly new technology for managing real and virtual storage. The CICS/VS products (CICS/OS/VS and CICS/DOS/VS) served the user community well but as CICS Development rapidly evolved the product during the 1973-1988 time period, it became clear that the product had to rearchitect itself in order to incorporate still more new technology.
With the new CICS/ESA Version 3 product CICS discontinued some old technology and moved into new functional areas for online systems. CICS users fared well as they moved from the original CICS product to the new world of virtual systems, and again, users migrated away from the old macro level days to the new command level only CICS environment, benefitting from the greater robustness of CICS/ESA.
The 1990s brought still another technology era for CICS. CICS responded well to the customer's need for greater system and application availability by its support of parallel systems, storage protection for both CICS and its applications, and incorporation of new technologies such as the coupling facility, automatic restart and more.
In the 1990s the CICS Transaction Server product (CICS TS) positioned itself to offer support for the emerging technologies. CICS evolved its support of the Internet by providing many ways by which the Internet user could access CICS applications and data. A web browser could access CICS directly, through an outboard server, or via the operating system and its interfaces such as the Common Gateway Interface (CGI).
CICS aggressively added support for Java so as to enable the user to benefit from the object oriented nature of the programming language. Applications written in Java are highly portable, suggesting they can be developed in one environment and yet used in another environment. Java applications, viewed as objects, brought the benefits of higher reusability of code. CICS made "write once, run anywhere" a reality.
The 1990s also brought other new technologies such as Enterprise Java Beans (EJB), IBM's introduction of the WebSphere product family and more comprehensive systems management software. The CICS TS product established the base from which CICS could support all these new software directions and put the user in a position to benefit from the newer technologies.
CICS began 1997 by delivering the Transaction Server for Windows NT Version 4. The reconstituted product was based on CICS for AIX 2.1.1 and incorporated all the function previously available with CICS for Windows NT V4. The new product also included client support for Windows NT and Windows 95, plus the CICS Gateway for Java for OS/2 and the CICS Gateway for Java for Windows NT. If the user wanted a comprehensive Windows-based transaction management system, this was it.
CICS continued its movement to UNIX platforms by introducing CICS for HP-UX Version 2.1.1. Hewlett-Packard originally provided a CICS capability with its CICS for HP9000 product but now HP deferred to IBM to provide the CICS support for the HP UNIX environment. CICS for HP-UX was a full function CICS, including such support as Intersystem Communications (ISC), External Presentation Interface (EPI) and External Call Interface (ECI). The new product was based on CICS for AIX 2.1.1.
IBM added to its VisualAge product line by delivering VisualAge for Java for OS/2 and Windows NT/95. The new compiler could be used to prepared Java application programs for use in CICS environments. VisualAge for Java included the Java Developer's toolkit (JDK 1.1) and the capability of producing Java Beans (objects, application programs, etc). VisualAge for Java enabled users to build CICS-related applications using EPI and ECI.
In June 1997, CICS announced an alternate pricing schedule for the CICSPlex System Management (CICSPlex SM) product. While the move appeared to respond to user requirements, the ultimate solution was to integrate the CICSPlex product into the base CICS TS product, which did occur sometime later.
CICSPlex SM did announce and deliver its 1.3 release in September 1997. The major enhancement was for something called Business Application Services (BAS), which was really Resource Definition Online (RDO) by another name. CICS had enhanced its command level interface with a new EXEC CICS CREATE capability which meant the user programs or vendor programs now had the ability to do RDO-like functions via a supported application programming interface (API). This is exactly what CICSPlex did in developing and delivering its BAS capability. The CICSPlex strategy was simple. In addition to providing services to manage a CICS configuration, it would also provide for the definition of resources to be used within that potentially multi-region, multi-machine configuration.
The major CICS announcement for 1997 was for the CICS TS for OS/390 Version 1 Release 2. The new release was delivered in October 1997 providing meaningful new support such as DASD Logging. CICS TS 1.1 replaced CICS' journal control facilities with the use of the new MVS Logger support. A number of users expressed concern that CICS TS then required a coupling facility for logging and requested that CICS provide a DASD-only logger facility, obviating the need for a coupling facility. This was now offered with CICS TS 1.2.
The other major enhancement delivered with CICS TS 1.2 was the introduction of the CICS 3270 Bridge. The Bridge would enable users to have web browsers connect directly to a CICS region and execute unchanged CICS 3270 applications, whether using Basic Mapping Support (BMS) or native terminal control (EXEC CICS TC commands). This new support complemented the already available CICS Web Interface (CWI) support which enabled browsers to execute COMMAREA-based applications.
In the DB2, CICS Development now took responsibility for developing and maintaining the CICS DB2 attachment code, plus providing RDO capability for defining DB2-related resources. CICS TS 1.2 also announced that TCP62 and AnyNet could now be used to enable LU6.2 data streams to flow over TCP/IP network connections. CICS TS 1.2 improved its support for high availability objectives with support of parallel systems, coupling facility usage and MVS' automatic recovery management (ARM).
The CICS TS 1.2 reiterated IBM's description of CICS as an Application Server, and announced that the new release was Year2000 Ready.
Late in 1997, IBM announced VSE/ESA 2.4 and contained within that announcement was the introduction of CICS Transaction Server for VSE/ESA. At this time, CICS had become more integrated with the VSE operating system. VSE 2.4 allowed users to run multiple versions of the operating system in one environment, which was previously not supported, but now was considered a major enhancement to assist users with release to release migration. CICS TS for VSE followed CICS/ESA's lead by discontinuing certain support such as the macro level interface, BTAM, RPG, DOS PL/I and C/370. CICS TS for VSE also discontinued direct access to CICS control blocks.
As always in the evolution of CICS and its product family, 1997 was a busy year, with CICS advancing on multiple fronts. Most notable was the expansion of CICS TS' capabilities and entry into the world of Java, object oriented systems and support of the Internet.
Copyright © 2004 - Yelavich Consulting, Sparks, NV
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